1. Field
The present invention relates to a touch system including an optical touch panel and a touch pen, and a method of controlling an interference optical signal in the touch system.
2. Description of the Related Art
In general, a touch screen is a screen that directly receives input data by recognizing a location of a human finger or an object contacting a particular location on the screen, and performing a predetermined process using software. To this end, a touch screen includes a touch panel attached to a general display panel, to perform its function.
Touch panels come in a variety of types, such as a resistive type, a capacitive type, a surface acoustic wave (SAW) type, an ultraviolet sensing type, and a piezoelectric type. Among these types, resistive type touch panels are widely employed as touch screens. Touch panels are implemented using a variety of methods. The price of a touch panel has been trending down, and thus, the use thereof has become popular. Also, multi-touch technology to recognize multiple contact points, and not simply one contact point, has enabled more diverse and natural operations. Recently, in-cell type touch screen panels, in which a touch sensor is integrated in pixels of a display panel, have been developed.